js ajax异步请求
2020-06-16 本文已影响0人
simplerandom
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<style>
#test-image-preview {
width: 1000px;
height: 1000px;
}
</style>
<body>
<input type="text" id="test-response-text" />
</body>
</html>
<script>
function success(text) {
var textarea = document.getElementById('test-response-text');
textarea.value = text;
}
function fail(code) {
var textarea = document.getElementById('test-response-text');
textarea.value = 'Error code: ' + code;
}
var request = new XMLHttpRequest(); // 新建XMLHttpRequest对象
request.onreadystatechange = function () { // 状态发生变化时，函数被回调
if (request.readyState === 4) { // 成功完成
// 判断响应结果:
if (request.status === 200) {
// 成功，通过responseText拿到响应的文本:
return success(request.responseText);
} else {
// 失败，根据响应码判断失败原因:
return fail(request.status);
}
} else {
// HTTP请求还在继续...
}
}
// 发送请求:
request.open('GET', 'http://new.toodo.fun/apis?type=contentWu&skey=3f239f68a035d40e1891d8b5fdf032d3');
request.send();
alert('请求已发送，请等待响应...');
</script>
